Category Archives: Branch Repeater

Top Ten VDI Mistakes (According to Dan Feller)

Dan Feller is a Lead Architect with the Citrix Consulting group, and has written extensively about XenDesktop. We found his series on the top ten mistakes people make when implementing desktop virtualization to be quite enlightening. In case you missed it, we thought we’d share his “top ten” list here, with links to the individual posts. We would highly recommend that you take the time to read through the series in its entirety:

#10 – Not calculating user bandwidth requirements
Back in the “good old days” of MetaFrame, when we didn’t particularly care about 3D graphics, multimedia content, etc., we could get by with roughly 20 Kbps of network bandwidth per user session. That’s not going to cut it for a virtualized desktop, for a number of reasons that Dan outlines in his blog post. He provides the following estimates for the average bandwidth required both with and without the presence of a pair of Citrix Branch Repeaters (which have some secret sauce that is specifically designed to accelerate Citrix traffic) between the client device and the virtual desktop session:

Parameter XenDesktop Bandwidth without Branch Repeater XenDesktop Bandwidth with Branch Repeater
Office Productivity Apps 43 Kbps 31 Kbps
Internet 85 Kbps 38 Kbps
Printing 553 – 593 Kbps 155 – 180 Kbps
Flash Video (with HDX redirection) 174 Kbps 128 Kbps
Standard WMV Video (with HDX redirection) 464 Kbps 148 Kbps
HD WMV Video (with HDX redirection) 1812 Kbps 206 Kbps

NOTE: These are estimates – your mileage may vary!

One thing that should come across loud and clear from the table above is what a huge difference the Citrix Branch Repeater can make in your bandwidth utilization. And as we’ve always said: you only buy hardware once – bandwidth costs go on forever!

#9 – Not considering the user profile
It should go without saying that user profiles are important. But if it’s number 9 on the list of things people most often screw up, then apparently it doesn’t. In a nutshell: If you mess up the users’ profiles, the users won’t be happy – logon/logoff performance will suffer, settings (including personalization) will be lost. If the users aren’t happy, they will be extremely vocal about it, and your VDI deployment will fail for lack of user buy-in and support. There are some great tools available for managing user profiles, including the Citrix Profile Manager, and the AppSense Environment Manager. AppSense can even maintain a consistent user experience across platforms – making sure that the user profile is the same regardless of whether the user is logged onto a Windows XP system, a Windows 7 System, or a Windows Server 2008 R2-based XenApp server.

Do yourself a favor and make sure you understand what your users’ profile requirements are, then investigate the available tools and plan accordingly.

#8 – Lack of an application virtualization strategy
How many applications are actually deployed in your organization? Do you even know? Are the versions consistent across all users? Which users use which applications? You have to understand the application landscape before you can decide how you’re going to deploy applications in your new virtualized desktop environment.

You have three basic choices on how to deliver apps:

  1. You can install every application into a single desktop image. That means that whenever an application changes, you have to change your base image, and do regression testing to make sure that the new or changed application didn’t break something else.
  2. You can create multiple desktop images with different application sets in each image, depending on the needs of your different user groups. Now if an application changes, you may have to change and do regression testing on multiple images. It’s worth noting that many organizations have been taking this approach in managing PC desktop images for years…but part of the promise of desktop virtualization is that, if done correctly, you can break out of that cycle. But to do that, you must…
  3. Remove the applications from the desktop image and deliver them some other way: either by running them on a XenApp server, or by streaming the application using either the native XenApp streaming technology or Microsoft’s App-V (or some other streaming technology of your choice).

Ultimately, you may end up with a mixed approach, where some core applications that everyone uses are installed in the desktop image, and the rest are virtualized. But, once again, it’s critical to first understand the application landscape within your organization, and then plan (and test) carefully to determine the best application delivery approach.

#7 – Improper resource allocation
Quoting Dan: “Like me, many users only consume a fraction of their total potential desktop computing power, which makes desktop virtualization extremely attractive. By sharing the resources between all users, the overall amount of required resources is reduced. However, there is a fine line between maximizing the number of users a single server can support and providing the user with a good virtual desktop computing experience.”

This post provides some great guidelines on how to optimize the environment, depending on the underlying hypervisor you’re planning to use.

#6 – Protection from Anti-Virus (as well as protection from viruses)
If you are provisioning desktops from a shared read-only image (e.g., Citrix Provisioning Services), then any virus infection will go away when the virtual PC is rebooted, because changes to the base image – including the virus – are discarded by design. But you still need AV protection, because the virus can use the interval between infection and reboot to propagate itself to other systems. The gotcha here is that the AV software itself can cause serious performance issues if it is not configured properly. Dan provides a great outline in this post for how to approach AV protection in a virtual desktop environment.

#5 – Managing the incoming storm
In most organizations, the majority of users arrive and start logging into their desktops at approximately the same time. What you don’t want is dozens, or hundreds, of virtual desktops trying to start up simultaneously, because it will hammer your virtualization environment. There are some very specific things you need to do to survive the “boot storm,” and Dan outlines them in this post.

#4 – Not optimizing the virtual desktop image
Dan provides several tips on things you should do to optimize your desktop image for the virtual environment. He also has specific sections on his blog that deal with recommended optimizations for Windows 7.

#3 – Not spending your cache wisely
Specifically, we’re talking about configuring the system cache on your Provisioning Server appropriately, depending on the OS and amount of RAM in your Provisioning Server, and the type of storage repository you’re using for your vDisk(s).

#2 – Using VDI defaults
Default settings are great for getting a small Proof of Concept up and running quickly. But as you scale up your VDI environment, there are a number of things you should do. If you ignore them, performance will suffer, which means that users will be upset, which means that your VDI project is more likely to fail.

#1 – Improper storage design
This shouldn’t be a surprise, because we’ve written about this before, and even linked to a Citrix TV video of Dan discussing this very thing as part of developing a reference architecture for an SMB (under 500 desktops) deployment. We’re talking here about how to calculate the “functional IOPS” available from a given storage system, and what that means in relation to the number of IOPS a typical user will need at boot time, logon time, working hours (which will vary depending on the users themselves), and logoff time.

Just to round things out, Dan also tossed in a few “honorable mentions,” like the improper use of NIC teaming or not optimizing the NIC configuration in Provisioning Servers, trying to provision images to hardware with mismatched hardware device drivers (generally not an issue if you’re provisioning into a virtual environment), and failing to have a good business reason for launching a VDI project in the first place.

Again, this post was intended to whet your appetite by giving you enough information that you’ll want to read through Dan’s individual “top ten” posts. We would heartily recommend that you do that – you’ll probably learn a lot. (We certainly did!)

The Future Is Now

I recently discovered a video on “Citrix TV” that does as good a job as I’ve ever seen in presenting the big picture of desktop and application virtualization using XenApp and XenDesktop (which, as we’ve said before, includes XenApp now). The entire video is just over 17 minutes long, which is longer than most videos we’ve posted here (I prefer to keep them under 5 minutes or so), but in that 17 minutes, you’re going to see:

  • How easy it is for a user to install the Citrix Receiver
  • Self-service application delivery
  • Smooth roaming (from a PC to a MacBook)
  • Application streaming for off-line use
  • A XenDesktop virtual desktop following the user from an HP Thin Client…
    • …to an iPad…
    • …as the iPad switches to 3G operation aboard a commuter train…
    • …to a Mac in the home office…
    • …to a Windows multi-touch PC in the kitchen…
    • …to an iPhone on the golf course.
  • And a demo of XenClient to wrap things up.

I remember, a few years ago, sitting through the keynote address at a Citrix conference and watching a similar video on where the technology was headed. But this isn’t smoke and mirrors, and it isn’t a presentation of some future, yet-to-be-released technology. All of this functionality is available now, and it’s all included in a single license model. The future is here. Now.

I think you’ll find that it’s 17 minutes that are well-spent:

Citrix Branch Repeater VPX Licensing Tutorial

I recently implemented both the new Citrix Access Gateway (CAG) VPX and the Branch Repeater VPX within our development lab. Both are “virtual appliances” designed to run directly on a XenServer host. Both are impressive products and work great – in fact, we can use “live motion” to move the CAG between XenServers while running video in a XenDesktop session with not even a pause in the video playback. The CAG moves with no interruption in service. NONE!

But this isn’t just a post to sing the praises of the virtual appliances. Rather, it’s about LICENSING!!! Specifically, licensing the Branch Repeater VPX.

As with many Citrix products, obtaining the license and getting it properly installed is not necessarily easy and intuitive…and in many cases (particularly with new products), we’ve found that the Citrix licensing support team does not know all the ins and outs of licensing a specific product either. That is not intended as a slam on this team. They do the best they can – but Citrix is a big company now, and sometimes it takes a while for information on new products to filter down to the front-line troops. In this case they worked with me for quite some time until we got this figured out (so there is at least one guy on the Citrix support team who now knows how this works).

So…now that I’ve gone through the pain, I thought I’d try to spare you from it if I can. (You’re welcome.)

One complication you’ll encounter is that, depending upon what you’re attempting to accomplish, these appliances may require one license or two. For example, with the CAG, if you are only going to use it for running secured sessions to a web interface (the equivalent of the legacy Citrix Secure Gateway) then you only need a “platform license.” However, if you also plan to run SSL VPN sessions though the CAG, you will need Access Gateway Universal licenses for your users, which will be rolled into a second license file.

Access Gateway licensing isn’t new and it’s pretty well understood. But what about the Branch Repeater? Just as with the CAG, the Branch Repeater may require one license or two, depending upon the functionality you need. If you are going to use the Branch Repeater VPX to connect to another (physical or virtual) Branch Repeater then you only need a platform license. However, if you want to take advantage of its ability to support client PCs that use the Branch Repeater Plug-in, you will need a second license to enable that feature. So we finally come to the topic of this post: how do you get the license file(s) onto your new Branch Repeater VPX?

First, you must log onto the “MyCitrix” web site with your account credentials, and access the Licensing Tool Box to activate and allocate the license. That part of the process is well documented, and if you’re a Citrix customer, you’ve probably done it at least once. The tricky part is what you have to do to download the VPX license file, what you need to enter in the Repeater itself, where to put it, and what you should see.

Here’s what we learned (NOTE: Click on any graphic to view full-sized):

  1. On the Branch Repeater VPX Web-based management interface, access the “Manage Licenses” screen, and in the right panel, choose “local” as shown below, and click the “Apply” button.
    License Server Configuration

    License Server Configuration

  2. Then click on the “License Information” tab and you will see something similar to this next image. What you will need from this screen is the “Local License Server Host Id:” Write down this information – you will need it in the next step.
    Information Used for License Management

    Information Used for License Management

  3. Now you can download the license file from your “MyCitrix” portal. Save it to your PC, and make a note of where you saved it. As part of the process of downloading the license, you must enter the license server ID. Traditionally, you would enter the name of the Citrix license server in this field (and it was case-sensitive, which tripped up a lot of users). But in this case, the system is expecting the MAC address of the Branch Repeater VPX itself…which is what you just copied in Step 2. Another difference is that in the past the License Server Host Type was always set to “HostName.” However, there is now a drop down box with a second choice, “ETHERNET.” For the Branch Repeater VPX, you want to select “ETHERNET,” and then enter the host id that you wrote down in Step 2:
    Downloading the License File from MyCitrix

    Downloading the License File from MyCitrix


    In case you’re wondering, the MAC address we’re using is the address of the first interface on the Branch Repeater VPX, as displayed in XenCenter. If you want to find it in XenCenter click on the VM in the left column and then select the Network tab in the right window and you should see it there:
    XenCenter Display

    XenCenter Display

  4. Now that you have your license downloaded to your local PC, you need to add it to your Branch Repeater. Access the “Local Licenses” tab and click the Add button (note that you will not see all the content in the window as shown here until you’ve added your license):
    Local Licenses Display

    Local Licenses Display


    After you click Add, this screen will appear and you will need to browse to the location where you saved your license file, and click the “Install” button:
    Add License

    Add License


    Now the “Local Licenses” tab should be populated with content:
    Local Licenses Display

    Local Licenses Display


    Next, go to the “Licensed Features” tab. You should see your features listed as shown below:
    Licensed Features

    Licensed Features

  5. As mentioned earlier, if you plan to support client PCs that have the Branch Repeater Plug-in, you will need another license to enable this feature. Once again you will need to go to your MyCitrix portal and follow the same procedure as you did for your platform license to obtain the Plug-in license. Once you have the Plug-in license you will need to add it to the Virtual Appliance in the same manner as you added the platform license. Once that’s done, if you click the down arrow under “Local Licenses” you will see both licenses:
    Manage Licenses Screen

    Manage Licenses Screen


    Finally, if you click the “Licensed Features” tab, both licenses should show up with the number of licenses available:
    Licensed Features

    Licensed Features

This should be all you need to get the Branch Repeater VPX licensed. Now you just need to get it configured correctly… but that’s another blog post.

Looking For the Citrix Acceleration Client for Win 7?

We’ve been working with the new Branch Repeater VPX virtual appliance, which supports the Branch Repeater client plug-in (unlike the hardware Branch Repeater appliances).

Since Moose Logic is a Microsoft Gold Partner, and we like to keep up with the latest releases, most of us have been running Windows 7 for a while now. But when we went looking for a Win7-compatible Branch Repeater plug-in for the Citrix Receiver, we had a tough time finding it.

It does exist, though, and now that we’ve tracked it down, we though we’d share with you just where it’s hiding in case you’ve been searching too.

The first thing to note is that, when you go to the Citrix download site, and search for downloads by product, you will see that the “Citrix Branch Repeater” and the “Citrix Repeater (formerly WANScaler)” are listed separately – and, since products are listed in alphabetical order, they’re quite a ways apart in the list (click on graphic to view full-size):

Downloads by Product

Downloads by Product


If you choose “Citrix Branch Repeater,” which is what we initially did, since we were working with the Branch Repeater VPX, the latest plug-in you will see listed is v5.0.34, which is not Win7-compatible:
v5.0.34

v5.0.34


So the secret is to choose “Citrix Repeater (formerly WANScaler)” from the product selection drop-down. Then you’ll see several later versions of the plug-in, including v5.5.2, which is Win7-compatible:
v5.5.2

v5.5.2


Oh, and if anyone from Citrix is reading this: Please – just get rid of the plug-ins listed under “Citrix Branch Repeater,” or, better yet, either have a redirect, or a line that says “Please see ‘Citrix Repeater (formerly WANScaler)’ for Branch Repeater plug-ins.” It will make life much simpler for everyone. Thank you.

Citrix Branch Repeater VPX Is Here

Earlier this month, we wrote about the Citrix push to virtualize many of their hardware appliances, the release of the Access Gateway VPX, and the pending release of a virtualized version of the Citrix Branch Repeater – their WAN optimization appliance.

The Branch Repeater VPX is now available. As you might expect, it is less expensive than its hardware counterparts, although, like its hardware counterparts, it is licensed based on the WAN bandwidth capacity it can handle. Here’s how it breaks down at the MSRP level:

Branch Repeater VPX Model 2 (2 Mbps): $4,000
Branch Repeater Model 200 (2 Mbps): $6,000

Branch Repeater VPX Model 10 (10 Mbps): $7,000
Branch Repeater Model 300 (10 Mbps): $10,000+ (depending on options)

Branch Repeater VPX Model 45 (45 Mbps): $13,000
Citrix Repeater 8540 (45 Mbps): $19,500

Furthermore, and this is a major change, all versions of the Branch Repeater VPX (even the $4,000 Model 2) will support the Branch Repeater Plug-in for the Citrix Receiver, meaning that they will accelerate connections from individual PC clients running the Repeater Plug-in. If you’re using physical appliances, you must, at a minimum, have a Citrix Repeater Model 8520, which lists for $11,500. That’s very good news for smaller customers.

As is the case with the Access Gateway VPX, the Branch Repeater VPX depends on the underlying HA functionality of XenServer to provide High Availability. (Note that Citrix has stated its intent to support other hypervisors, but the initial release is only supported on XenServer.)

There is also no indication that there will be a virtualized version of the Branch Repeater with Windows Server (hereafter the “BRwWS” to conserve electrons). After a bit of reflection, that probably makes sense. After all, the BRwWS is intended for customers who need to support services like Domain authentication, DNS, DHCP, print services, etc., at branch offices, but do not want to place traditional servers there. If you’re running a virtual appliance, then, by definition, you have at least one (and probably more than one) virtual host at that location. Therefore you are already supporting traditional server hardware there. And you probably already have other virtual servers running on those hosts and providing the needed services (and if you don’t it’s easy enough to stand one up).

One final note about the BRwWS, while we’re on the subject: Branch Repeater with Windows Server 2008 is now available. Therefore, the Branch Repeater with Windows Server 2003 will no longer be sold as of July 31, 2010.